Clean the vegetables well. Shred the lettuce and iceberg lettuce in a large bowl. Add the cauliflowers, the ham and cheese, sliced into thin strips, to them and gently mix.
Prepare a dressing for the salad by mixing together the yoghurt, soya sauce, olive oil and lemon juice. Pour it over the salad in the bowl.
Serve in individual plates, sprinkle with salt and pepper to taste.